Rat bite fever due to Streptobacillus notomytis complicated by meningitis and spondylodiscitis: a case report

Abstract

Background Only three other cases of rat bite fever caused by Streptobacillus notomytis in humans have been reported since this species was identified in 2015. Data specific to the differences in clinical features and geographic distribution between S. notomytis infection and S. moniliformis infection are scarce. All previous cases of human S. notomytis infection were reported from Japan. This is the first case of S. notomytis infection reported from outside of Japan. Case presentation A 72-year-old Thai woman was admitted to Siriraj Hospital (Bangkok, Thailand)—Thailand’s largest university-based national tertiary referral center—in August 2020 with fever, myalgia, and polyarthralgia for 3 days, and gradually decreased consciousness for the past 1 day. Physical examination and laboratory investigations revealed septic arthritis of both knee joints, meningitis, and hepatitis. She was initially misdiagnosed as rheumatoid arthritis in the elderly since the initial investigations were unable to detect a causative pathogen. However, S. notomytis infection was later confirmed by polymerase chain reaction amplification of a part of the 16S rRNA gene and sequencing from synovial fluid. Her clinical course was also complicated by spondylodiscitis and epidural abscess caused by S. notomytis, which was detected from tissue biopsy. Therefore, rat bite fever in this patient manifested as meningitis, septic polyarthritis, hepatitis, and spondylodiscitis. The patient was treated with intravenous ceftriaxone then switched to oral amoxicillin with complete recovery. Conclusions The clinical manifestations of S. notomytis infection are similar to those demonstrated in S. moniliformis infection. This case also showed that arthritis caused by S. notomytis mimics rheumatoid arthritis, and that meningitis and spondylodiscitis are potential coexisting complications that can be found in S. notomytis infection.

Rat Bite Fever Human Disease

“…Rat Bite Fever is typically asymptomatic in carrier rats, but secondary bacterial pulmonary infections and abscesses can be absorbed sporadically. The pathogenicity of the disease changes depending on the strain of bacteria in rats, and affected rats may develop prolonged septicemia, leading to sudden death (Pongsuttiyakorn et al 2021). The typical clinical signs of Rat Bite Fever include weight loss, hemoglobinuria, cyanosis, conjunctivitis, cervical lymphadenitis, and diarrhea.…”

“…The clinical signs of infections caused by S. notomytis are characterized by fever, rashes, polyarthritis, hepatitis, meningitis, and spondylodiscitis which are also common (Kusuda et al 2020;Pongsuttiyakorn et al 2021). S. minus bacteria cause rat bite infections in the Middle East which are referred to as Sodoku.…”

Rat bite fever, a neglected and underdiagnosed entity: case report

“…2,5 In the last decade four novel species have been described, which have been named Streptobacillus canis, Streptobacillus notomytis, Streptobacillus felis, and Streptobacillus ratti, with few cases reported to be caused by these species, especially with S. notomytis. 6 The following is a description of the disease and a clinical case of a patient diagnosed with rat bite fever.…”

Rat bite fever caused by Streptobacillus notomytis mimicking pyogenic polyarthritis: A case report

“…Rat bite fever is a rare disease that is found mainly in Asian countries [1] , [2] , [3] , [4] , [5] . The classical manifestations include acute relapsing fever, rash, and migratory polyarthralgia [1] , [6] .…”

“…In 2018, the first human case of rat bite fever caused by S. notomytis was reported in Okinawa, Japan [1] . Until now, there were only five case reports of rat bite fever caused by S. notomytis [1] , [2] , [3] , [4] , [5] . Streptobacillus sp.…”